This invention relates to a head-mounted display device for visually recognizing images output from personal computers, television images, and images displayed by display devices for performing various kinds of work, which is mounted on the head as a wearable personal computer display device, for example.
In recent years, information devices typified by the wearable personal computer, which mounts computer functions on the human body, are being practically implemented. These devices function as auxiliary equipment when performing complex work or making decisions requiring sophisticated knowledge at the job site. By using the head-mounted display device as a monitor for such wearable personal computers, the images on that monitor can be visually recognized while working on the job.
Such a head-mounted display device is known that has a structure wherein a display unit comprising a display deployed at the side of the head or above or below the eyeballs and a non-spherical reflecting optical system for causing the images displayed on that display to be visually recognized is fixed to the head by a headphone type mounting unit.
There is a problem with the conventional head-mounted display device in that the display unit, being large, places a burden on the user. The conventional scheme proposed for resolving this problem is to provide an arm that sticks out to the side in a holder that extends from the sides of the head to the back of the head, and then secure the display unit to that arm. Based on this scheme it is possible to make the holder and the display smaller.
However, with this conventional scheme, the interval between the display device and the eyes becomes great to some extent because the display unit is secured to the arm that protrudes from the side of the holder. This entails a problem in that the display unit becomes large when the visual field angle is made large. When a small, lightweight display unit is used in this conventional scheme, it is very difficult to visually recognize the small details of sophisticated personal computer output images (such as color SVGA images having a resolution of 800xc3x97600 dots, for example).
Also, when the conventional scheme is applied to a monocular head-mounted display device having a single display, the position of the display unit must be changed from left to right or right to left according to the user""s needs (i.e., according to which side the vision of the user is better on, whether the user is right-sighted or left-sighted, user preference, etc.). For that reason, it is necessary to temporarily remove the display unit from the holder, invert the holder, and reattach the display unit to the holder. Because the display unit is fastened to the holder by screws or the like, one must use a screwdriver or similar tool to detach and reattach the display unit. Thus it is not possible for a user to frequently change the display unit back and forth between the right and left sides according to his or her preference, etc., making the utility of the device very poor. In short, what is needed is a configuration wherewith the display unit can be stably held in place and the position of the display unit can easily be changed between left and right. Furthermore, because there are great personal differences between users in terms of facial shape (such as the shape of the eye sockets and the slope of the forehead), a configuration is also necessary wherewith the position of the display unit can be adjusted fore and aft in order to optimally adjust the interval between the eyeballs and the display unit.
An object of the present invention is to provide a head-mounted display device wherewith a visual field angle can be secured that will enable adequate recognition of display image information, wherewith the user can freely choose which eye to use to visually recognize the display image, wherewith the display unit can be easily positioned for optimum visual recognition of the display image, and wherewith the display unit can be easily attached and detached.
The head-mounted display device of the present invention comprises: a head holding holder that is proximate at least to both sides of the head and the front of the head; and a display unit deployed on the holder at a position above the eye either on the left or the right side, at the front of the head.
It is preferable that the holder is capable of being used inverted.
It is preferable that the holder has a shape capable of preventing head holding force thereof from becoming unbalanced to the left or the right.
By preventing the head holding force of this holder from becoming unbalanced to the left or right, the holding force acting on the head of the user from the left side and the holding force acting thereon from the right side become roughly the same. Thus, even when the holder is inverted, differences in the holding force acting from the left thereof and the holding force acting from the right thereof that are sensible to the user can be prevented from occurring. The holding force acting from the left side and the holding force acting from the right side need only be roughly the same, to such an extent that the user will not sense a difference in left and right holding force.
There is no particular limitation on the shape of the holder, and it need only contact at least the two sides of the head and the front of the head. That shape can be a U shape as in a head band or hair band, for example, or it can be ring shaped. The parts of the holder that are proximate to the head are not limited to those parts proximate to the two sides of the head and the front of the head; there can also be a part proximate to the crown of the head, in which case a cap shape, for example, can be adopted as the shape of the holder.
The shape of the holder is not limited to one that is laterally symmetrical. When the holder weight is laterally asymmetrical, for example, the shapes of the parts of the holder proximate to the front of the head and to two sides of the head can be mutually different so that the holding force acting on the head of the user from the left side is roughly the same as the holding force acting thereon from the right side.
By the holder being xe2x80x9cproximatexe2x80x9d to the head, in the present invention, is meant not only cases where the holder makes direct contact with the two sides of the head and the front of the head, but also cases where it makes indirect contact therewith through an intermediate material such as a head protecting member (described subsequently), for example.
The holder can be configured by a single member. Alternatively, the holder can be divided between a member that is proximate to one side of the head, a member that is proximate to the other side of the head, and a member that is proximate to the front of the head, with a hinge structure both between the member proximate to the front of the head and the member proximate to the one side of the head and between the member proximate to the front of the head and the member proximate to the other side of the head.
A head protecting member can be provided on the holder at an area near the front of the head and/or at a part of area extending from the sides of the head to the back of the head. Such a head protecting member can consist of a so-called pad or other shock absorbing material. The material of the head protecting member can be anything that exhibits elasticity, such as a urethane sponge, elastomer, or rubber. This head protecting member can be made either integrally with the holder or separately therefrom.
The display unit is configured by a display that creates at least a display image and a reflecting optical member having a reflecting surface that reflects display light output from the display. A liquid crystal display device, plasma display, or small CRT display or the like can be used for this display, but such does not constitute a limitation. The liquid crystal display device can be either a transmitting type or reflecting type. The light source therefor can be either a surface light source or a point light source, and a LED, halogen bulb, or cold cathode tube, etc., can be used, for example.
The reflecting optical member can be configured by combining a full reflecting mirror, half mirror, and/or prism or the like.
Inside the display unit, drive means such as a circuit board for receiving signals from an external signal source and driving the display device can be comprised. That circuit board can also be provided separately from the display unit.
The display unit is attachable in a position either on the left or the right of the holder, on the side at the front of the head, in a position above the eye of the user. Thus the display device unit hangs down from the vicinity of one of the eyebrows, and so approaches near to the eyeball. Thus, even if the display unit is small, it can be securely held so that it poses but a small obstacle in the field of view, so that a suitable visual field angle can be guaranteed. By the xe2x80x9cposition above the eyexe2x80x9d wherein this display unit should be deployed is signified a position wherewith the light emitted from the display unit subtends an angle of 0 to xc2x145 degrees, in the vertical direction, with the horizontal plane that contains the line of sight of the user to the front, and wherein the emitted light subtends an angle of 0 to xc2x160 degrees, in the lateral direction, with the vertical plane that includes the line of sight of the user toward the front.
The display unit is attached to the holder so that it can be inverted. It is preferable that the attachment of the display unit to the holder is done so that attachment and detachment are easy. For example, a display unit holding guide is provided in the holder and making the display unit capable of sliding relative to such guide. There is no limitation to such a configuration, however, and the display unit can be attached to the holder with screws or the like.
Alternatively, it is preferable that parts for mutually joining the display unit and the holder each have a vertically symmetrical shape. Or, a display unit holding guide can be provided in the holder and the display unit made so that it can turn about an axis oriented in a direction in which the guide protrudes. In that case, a configuration can be implemented wherein a cutout is made in the guide so that the display unit can be inverted relative to the holder when it is positioned near the tip of the guide. The position of the display unit can be switched from left to right or right to left, by inverting the display unit relative to the holder and then inverting the holder relative to the user.
In the head-mounted display device of the present invention, it is preferable that left to right movement means, up and down movement means, and fore and aft movement means be provided so that the display unit described in the foregoing can be adjustably moved left and right, up and down, and fore and aft relative to the holder described in the foregoing.
The holder can consist, for example, of a holding cover for holding the display unit and a frame for supporting the holding cover. Guide channels can be formed in the holding cover for the up and down movement means. The frame can have a shape that is vertically symmetrical.
It is preferable that the left and right movement means, up and down movement means, and fore and aft movement means have a shaft-shaped guide structure respectively. A preferable structure for up and down movement means having such a shaft-shaped guide structure is one wherein the display unit is linked via a pin to the holding cover described above, which pins are made movable along a guide channel in the holding cover, but this does not constitute a limitation. The left and right movement means can be such that the display unit is held so that it can turn about the shaft of the shaft-shaped guide structure. For example, a structure is conceivable wherein a guide shaft is provided in the frame described above, the display unit is attached to that guide shaft, either directly or indirectly through the holding cover, and the display unit is made moveable to the left and right along that guide shaft, but this poses no limitation. A structure is conceivable for the fore and aft movement means wherein, for example, a fore and aft guide plate extending in the fore and aft directions are provided in a left and right guide shaft, and the display unit is moved along the fore and aft guide plate, either directly or integrally with the holding cover, but this poses no limitation.
When the display unit does not come into the visual field angle of the user, the position of the display unit is finely adjusted by the left and right movement means, up and down movement means, and fore and aft movement means. The amount of movement induced in the display unit by those left and right movement means, up and down movement means, and fore and aft movement means is preferably from 0 to xc2x110 mm in the left and right direction, 0 to xc2x110 mm in the up and down direction, and 0 to xc2x110 mm in the fore and aft direction. When the position of the display unit is adjusted so as to exceed these movement amounts, the adjustment is made by moving the holder itself.
The display unit is positionally adjusted in the yaw direction, roll direction, and pitch direction by moving the holder relative to the head.
It is preferable that the left and right movement means, up and down movement means, and fore and aft movement means have movement guidance mating parts, respectively, and that the display unit described above has a play to move slightly relative to the holder in at least one of those movement guidance mating parts. Thus the position of the display unit can be finely adjusted in the yaw direction, roll direction, and pitch direction. In the up and down movement means having the shaft-shaped guide structure described above, the guide channel described above correspond to the movement guidance mating part.
It is preferable that the left and right movement means have a shaft-shaped guide structure, and display retraction means are provided for holding the display unit so that the display unit can turn about a shaft of that shaft-shaped guide structure, or for holding the display unit so that the display unit is moveable to the left and right along the shaft of that shaft-shaped guide structure. The amount of the turning or left and right movement of the display unit is determined so that the display unit can be removed from the field of view of the user.
It is preferable, in the head-mounted display device of the present invention, that display unit attachment and detachment means be provided for attaching and detaching the holder to and from the display unit without using any tools.
The display unit attachment and detachment means are for attaching and detaching the display unit to and from the holder without using any tools. By xe2x80x9cnot using any toolsxe2x80x9d is meant that the display unit can be attached and detached by hand, without using a screw driver or other tightening tool. More specifically, it is preferable that the display unit attachment and detachment means have a dial wherewith a turning manipulation is possible, such that the display unit can be attached to and detached from the holder by turning manipulation with that dial. It is preferable that the dial be knurled about its outer circumference. The display unit can also be attached to and detached from the holder by using a spring, a slide channel, etc.
The display device of the present invention can be used for displaying job content at manufacturing plants or assembly plants for various kinds of products, for displaying English conversation or other educational information, and for displaying items on display at tourist attractions, historic sites, aquariums, botanical gardens, or showrooms, etc.
According to the present invention, a head-mounted display device can be realized wherewith images can be visually recognized at a practical level of display viewing range angle, with small size and light weight, with ease of mounting, and with either the left or right eye, wherewith the display position can be easily adjusted for optimum visual recognition, wherewith the display unit can be positionally adjusted up and down, to the left and right, and fore and aft, with a simple configuration, wherewith the display unit can be retracted beyond the range of the field of view when not being used, and wherewith the display unit can be easily attached and detached simply by turning a dial, without using any special tools.